And it looks increasingly likely he will draw a line under his incredible F1 career.

On Tuesday, the former champions from Grove were ruled out as an option.

Insiders at Williams say lots of work has been going on behind the scenes and significant technical announcements are expected in the coming months.

Brawn had been strongly linked with Williams because he is held in high esteem by its current technical director Pat Symonds, a former Benetton colleague during their title-winning years with Michael Schumacher.

He had also been linked to McLaren, but both sides denied there had been talks.

That means his only option, if he is to stay in F1, is to re-unite with car giant Honda, returning as McLaren’s power supplier in 2015.

Sources said Brawn, 58, had decided to quit Brackley after tiring of long-running talks with Mercedes new management.

He warned he would only be prepared to stay if he was in overall technical control – which insiders ruled out because of the arrival of Paddy Lowe from McLaren.

Brawn made over £100m from the sale of the team which bore his name to Mercedes after winning the world title with Jenson Button in 2009.